title: A comparative picosecond transient infrared study of 1-methylcytosine and 5'-dCMP that sheds further light on the excited states of cytosine derivatives.
abstract: The role of N1-substitution in controlling the deactivation processes in photoexcited cytosine derivatives has been explored using picosecond time-resolved IR spectroscopy. The simplest N1-substituted derivative, 1-methylcytosine, exhibits relaxation dynamics similar to the cytosine nucleobase and distinct from the biologically relevant nucleotide and nucleoside analogues, which have longer-lived excited-state intermediates. It is suggested that this is the case because the sugar group either facilitates access to the long-lived (1)n(O)π* state or retards its crossover to the ground state.
authors.affiliation: School of Chemistry and Centre for Synthesis and Chemical Biology, Trinity College, Dublin 2, Ireland.
authors.forename: Páraic M
authors.initials: PM
authors.lastname: Keane
authors.forename: Michal
authors.initials: M
authors.lastname: Wojdyla
authors.forename: Gerard W
authors.initials: GW
authors.lastname: Doorley
authors.forename: Graeme W
authors.initials: GW
authors.lastname: Watson
authors.forename: Ian P
authors.initials: IP
authors.lastname: Clark
authors.forename: Gregory M
authors.initials: GM
authors.lastname: Greetham
authors.forename: Anthony W
authors.initials: AW
authors.lastname: Parker
authors.forename: Michael
authors.initials: M
authors.lastname: Towrie
authors.forename: John M
authors.initials: JM
authors.lastname: Kelly
authors.forename: Susan J
authors.initials: SJ
authors.lastname: Quinn
mesh_terms: D003596:Cytosine / Q000031:analogs & derivatives* / Q000737:chemistry*; D003843:Deoxycytidine Monophosphate / Q000737:chemistry*; D008027:Light; D013055:Spectrophotometry, Infrared
chemical_list: D003843:Deoxycytidine Monophosphate; C031532:1-methylcytosine; D003596:Cytosine